Chemistry

Problem

Calculate

E^\circ

of redox change:

\text{Ag}_2\text{S} + 2e^- \rightleftharpoons 2\text{Ag} + \text{S}^{2-}

if the reaction occurs at pH

= 3

and is saturated with

0.1\,\text{M}

\text{H}_2\text{S}

K_1

and

K_2

for

\text{H}_2\text{S}

are

1 \times 10^{-8}

and

1.1 \times 10^{-13}

respectively.

K_{\text{sp}}(\text{Ag}_2\text{S}) = 2 \times 10^{-49}

and

E_{\text{Ag}^+/\text{Ag}}^\circ = 0.8\,\text{V}